Summary

The documentation and integration of heterogeneous digital data produced by
different communities with varying practices, assumptions, representation schemes, and encodings, presents substantial obstacles to integration and
analysis. Developing conceptual models for these notions raises foundational issues in the representation of information in digital form, many pertaining to
identity. In this paper we present the Basic Representation Model and the Systematic Assertion Model. We show how these models work together to provide
an analytical account of digitally-encoded scientific data. We expect these models to inform precisely defined
format-migration activities, assessment of identity and scientific equivalence, and digital preservation strategies in
general.